1. Field of the Invention
This invention is related to the solderless termination of insulated or uninsulated electrical conductors by utilizing slotted plate-like terminals to penetrate the insulation and establish intimate contact with the underlying conductive core. This invention is also related to the installation of various electrical components such as duplex outlet receptacles in the electrical wiring of a building such as a house or mobile home.
2. Description of the Prior Art
Standard electrical wiring devices and fixtures such as outlet receptacles and switches currently used for residential and related electrical wiring generally employ a screw-down wire termination. Installation of these standard prior art devices on standard three wire sheathed non-metallic cables requires several steps. The cable must first be severed. The outer sheath surrounding the two current carrying and the ground wires must be removed. Next the insulation on the end of the hot and neutral conductors must be stripped. The stripped wires are then looped around individual screws which are then tightened in order to secure the wires. The completed assembly together with necessary slack wire must then be stuffed into a standard box mounted within the walls.
A number of modifications to this approach have been suggested. One such modification representative of other approaches is found in U.S. Pat. No. 3,860,739. These duplex receptacles and switches can be mounted by utilizing a hand tool to form the wires in a non-metallic sheathed cable and to insert the wires into slotted plate electrical terminals. The back cover of these receptacles or switches is subsequently mated with the front portion to force the conductors into their respective slotted contacts, automatically penetrating the insulation and making intimate contact between the conductors and the receptacle and switch contact. The cover locks in place maintaining the electrical and mechanical integrity of the connection.
Another principle that can be utilized to terminate electrical conductors in an electrical wiring assembly is illustrated by U.S. Pat. No. 3,489,985. Duplex receptacles employing this concept utilized poke-in type terminals. These poke-in terminals require stripping the insulation from the ends of the individual conductors prior to termination. Spring-type wire fastening means are employed to grip conductors which have been inserted between the spring members and an appropriate backup surface. The spring is flexed or cammed by the entry of the stripped conductors and one edge of the spring establishes an electrical contact with the inserted wire.
Numerous slotted members have been proposed for solderless termination of insulated or uninsulated electrical conductors. In addition to the solderless termination means employed in the previously described prior art, stamped and formed terminals having a central segment removed to define a slot with opposed wire gripping edges and the plane of the terminal have been widely used. Another slotted plate type termination of interest is shown in U.S. Pat. No. 3,162,501. In this patent lances have been struck from opposite sidewalls of a U-shaped plate-like member. As an insulated conductor is inserted into the U-shaped member these inwardly deflected lances penetrate the insulation and establish intimate contact with the underlying conductive core.